4 * Copyright (C) 2000 Eric Youngdale,
5 * Copyright (C) 2002 Patrick Mansfield
7 * The general scanning/probing algorithm is as follows, exceptions are
8 * made to it depending on device specific flags, compilation options, and
9 * global variable (boot or module load time) settings.
11 * A specific LUN is scanned via an INQUIRY command; if the LUN has a
12 * device attached, a scsi_device is allocated and setup for it.
14 * For every id of every channel on the given host:
16 * Scan LUN 0; if the target responds to LUN 0 (even if there is no
17 * device or storage attached to LUN 0):
19 * If LUN 0 has a device attached, allocate and setup a
22 * If target is SCSI-3 or up, issue a REPORT LUN, and scan
23 * all of the LUNs returned by the REPORT LUN; else,
24 * sequentially scan LUNs up until some maximum is reached,
25 * or a LUN is seen that cannot have a device attached to it.
28 #include <linux/module.h>
29 #include <linux/moduleparam.h>
30 #include <linux/init.h>
31 #include <linux/blkdev.h>
32 #include <linux/delay.h>
33 #include <linux/kthread.h>
34 #include <linux/spinlock.h>
35 #include <linux/async.h>
36 #include <linux/slab.h>
38 #include <scsi/scsi.h>
39 #include <scsi/scsi_cmnd.h>
40 #include <scsi/scsi_device.h>
41 #include <scsi/scsi_driver.h>
42 #include <scsi/scsi_devinfo.h>
43 #include <scsi/scsi_host.h>
44 #include <scsi/scsi_transport.h>
45 #include <scsi/scsi_eh.h>
47 #include "scsi_priv.h"
48 #include "scsi_logging.h"
50 #define ALLOC_FAILURE_MSG KERN_ERR "%s: Allocation failure during" \
51 " SCSI scanning, some SCSI devices might not be configured\n"
56 #define SCSI_TIMEOUT (2*HZ)
59 * Prefix values for the SCSI id's (stored in sysfs name field)
61 #define SCSI_UID_SER_NUM 'S'
62 #define SCSI_UID_UNKNOWN 'Z'
65 * Return values of some of the scanning functions.
67 * SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
68 * includes allocation or general failures preventing IO from being sent.
70 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
73 * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
76 #define SCSI_SCAN_NO_RESPONSE 0
77 #define SCSI_SCAN_TARGET_PRESENT 1
78 #define SCSI_SCAN_LUN_PRESENT 2
80 static const char *scsi_null_device_strs = "nullnullnullnull";
82 #define MAX_SCSI_LUNS 512
84 #ifdef CONFIG_SCSI_MULTI_LUN
85 static unsigned int max_scsi_luns = MAX_SCSI_LUNS;
87 static unsigned int max_scsi_luns = 1;
90 module_param_named(max_luns, max_scsi_luns, uint, S_IRUGO|S_IWUSR);
91 MODULE_PARM_DESC(max_luns,
92 "last scsi LUN (should be between 1 and 2^32-1)");
94 #ifdef CONFIG_SCSI_SCAN_ASYNC
95 #define SCSI_SCAN_TYPE_DEFAULT "async"
97 #define SCSI_SCAN_TYPE_DEFAULT "sync"
100 static char scsi_scan_type[6] = SCSI_SCAN_TYPE_DEFAULT;
102 module_param_string(scan, scsi_scan_type, sizeof(scsi_scan_type), S_IRUGO);
103 MODULE_PARM_DESC(scan, "sync, async or none");
106 * max_scsi_report_luns: the maximum number of LUNS that will be
107 * returned from the REPORT LUNS command. 8 times this value must
108 * be allocated. In theory this could be up to an 8 byte value, but
109 * in practice, the maximum number of LUNs suppored by any device
112 static unsigned int max_scsi_report_luns = 511;
114 module_param_named(max_report_luns, max_scsi_report_luns, uint, S_IRUGO|S_IWUSR);
115 MODULE_PARM_DESC(max_report_luns,
116 "REPORT LUNS maximum number of LUNS received (should be"
117 " between 1 and 16384)");
119 static unsigned int scsi_inq_timeout = SCSI_TIMEOUT/HZ + 18;
121 module_param_named(inq_timeout, scsi_inq_timeout, uint, S_IRUGO|S_IWUSR);
122 MODULE_PARM_DESC(inq_timeout,
123 "Timeout (in seconds) waiting for devices to answer INQUIRY."
124 " Default is 20. Some devices may need more; most need less.");
126 /* This lock protects only this list */
127 static DEFINE_SPINLOCK(async_scan_lock);
128 static LIST_HEAD(scanning_hosts);
130 struct async_scan_data {
131 struct list_head list;
132 struct Scsi_Host *shost;
133 struct completion prev_finished;
137 * scsi_complete_async_scans - Wait for asynchronous scans to complete
139 * When this function returns, any host which started scanning before
140 * this function was called will have finished its scan. Hosts which
141 * started scanning after this function was called may or may not have
144 int scsi_complete_async_scans(void)
146 struct async_scan_data *data;
149 if (list_empty(&scanning_hosts))
151 /* If we can't get memory immediately, that's OK. Just
152 * sleep a little. Even if we never get memory, the async
153 * scans will finish eventually.
155 data = kmalloc(sizeof(*data), GFP_KERNEL);
161 init_completion(&data->prev_finished);
163 spin_lock(&async_scan_lock);
164 /* Check that there's still somebody else on the list */
165 if (list_empty(&scanning_hosts))
167 list_add_tail(&data->list, &scanning_hosts);
168 spin_unlock(&async_scan_lock);
170 printk(KERN_INFO "scsi: waiting for bus probes to complete ...\n");
171 wait_for_completion(&data->prev_finished);
173 spin_lock(&async_scan_lock);
174 list_del(&data->list);
175 if (!list_empty(&scanning_hosts)) {
176 struct async_scan_data *next = list_entry(scanning_hosts.next,
177 struct async_scan_data, list);
178 complete(&next->prev_finished);
181 spin_unlock(&async_scan_lock);
187 /* Only exported for the benefit of scsi_wait_scan */
188 EXPORT_SYMBOL_GPL(scsi_complete_async_scans);
192 * For async scanning we need to wait for all the scans to complete before
193 * trying to mount the root fs. Otherwise non-modular drivers may not be ready
196 late_initcall(scsi_complete_async_scans);
200 * scsi_unlock_floptical - unlock device via a special MODE SENSE command
201 * @sdev: scsi device to send command to
202 * @result: area to store the result of the MODE SENSE
205 * Send a vendor specific MODE SENSE (not a MODE SELECT) command.
206 * Called for BLIST_KEY devices.
208 static void scsi_unlock_floptical(struct scsi_device *sdev,
209 unsigned char *result)
211 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
213 printk(KERN_NOTICE "scsi: unlocking floptical drive\n");
214 scsi_cmd[0] = MODE_SENSE;
218 scsi_cmd[4] = 0x2a; /* size */
220 scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE, result, 0x2a, NULL,
221 SCSI_TIMEOUT, 3, NULL);
225 * scsi_alloc_sdev - allocate and setup a scsi_Device
226 * @starget: which target to allocate a &scsi_device for
228 * @hostdata: usually NULL and set by ->slave_alloc instead
231 * Allocate, initialize for io, and return a pointer to a scsi_Device.
232 * Stores the @shost, @channel, @id, and @lun in the scsi_Device, and
233 * adds scsi_Device to the appropriate list.
236 * scsi_Device pointer, or NULL on failure.
238 static struct scsi_device *scsi_alloc_sdev(struct scsi_target *starget,
239 unsigned int lun, void *hostdata)
241 struct scsi_device *sdev;
242 int display_failure_msg = 1, ret;
243 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
244 extern void scsi_evt_thread(struct work_struct *work);
245 extern void scsi_requeue_run_queue(struct work_struct *work);
247 sdev = kzalloc(sizeof(*sdev) + shost->transportt->device_size,
252 sdev->vendor = scsi_null_device_strs;
253 sdev->model = scsi_null_device_strs;
254 sdev->rev = scsi_null_device_strs;
256 sdev->queue_ramp_up_period = SCSI_DEFAULT_RAMP_UP_PERIOD;
257 sdev->id = starget->id;
259 sdev->channel = starget->channel;
260 sdev->sdev_state = SDEV_CREATED;
261 INIT_LIST_HEAD(&sdev->siblings);
262 INIT_LIST_HEAD(&sdev->same_target_siblings);
263 INIT_LIST_HEAD(&sdev->cmd_list);
264 INIT_LIST_HEAD(&sdev->starved_entry);
265 INIT_LIST_HEAD(&sdev->event_list);
266 spin_lock_init(&sdev->list_lock);
267 INIT_WORK(&sdev->event_work, scsi_evt_thread);
268 INIT_WORK(&sdev->requeue_work, scsi_requeue_run_queue);
270 sdev->sdev_gendev.parent = get_device(&starget->dev);
271 sdev->sdev_target = starget;
273 /* usually NULL and set by ->slave_alloc instead */
274 sdev->hostdata = hostdata;
276 /* if the device needs this changing, it may do so in the
277 * slave_configure function */
278 sdev->max_device_blocked = SCSI_DEFAULT_DEVICE_BLOCKED;
281 * Some low level driver could use device->type
286 * Assume that the device will have handshaking problems,
287 * and then fix this field later if it turns out it
292 sdev->request_queue = scsi_alloc_queue(sdev);
293 if (!sdev->request_queue) {
294 /* release fn is set up in scsi_sysfs_device_initialise, so
295 * have to free and put manually here */
296 put_device(&starget->dev);
300 blk_get_queue(sdev->request_queue);
301 sdev->request_queue->queuedata = sdev;
302 scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
304 scsi_sysfs_device_initialize(sdev);
306 if (shost->hostt->slave_alloc) {
307 ret = shost->hostt->slave_alloc(sdev);
310 * if LLDD reports slave not present, don't clutter
311 * console with alloc failure messages
314 display_failure_msg = 0;
315 goto out_device_destroy;
322 __scsi_remove_device(sdev);
324 if (display_failure_msg)
325 printk(ALLOC_FAILURE_MSG, __func__);
329 static void scsi_target_destroy(struct scsi_target *starget)
331 struct device *dev = &starget->dev;
332 struct Scsi_Host *shost = dev_to_shost(dev->parent);
335 transport_destroy_device(dev);
336 spin_lock_irqsave(shost->host_lock, flags);
337 if (shost->hostt->target_destroy)
338 shost->hostt->target_destroy(starget);
339 list_del_init(&starget->siblings);
340 spin_unlock_irqrestore(shost->host_lock, flags);
344 static void scsi_target_dev_release(struct device *dev)
346 struct device *parent = dev->parent;
347 struct scsi_target *starget = to_scsi_target(dev);
353 static struct device_type scsi_target_type = {
354 .name = "scsi_target",
355 .release = scsi_target_dev_release,
358 int scsi_is_target_device(const struct device *dev)
360 return dev->type == &scsi_target_type;
362 EXPORT_SYMBOL(scsi_is_target_device);
364 static struct scsi_target *__scsi_find_target(struct device *parent,
365 int channel, uint id)
367 struct scsi_target *starget, *found_starget = NULL;
368 struct Scsi_Host *shost = dev_to_shost(parent);
370 * Search for an existing target for this sdev.
372 list_for_each_entry(starget, &shost->__targets, siblings) {
373 if (starget->id == id &&
374 starget->channel == channel) {
375 found_starget = starget;
380 get_device(&found_starget->dev);
382 return found_starget;
386 * scsi_target_reap_ref_release - remove target from visibility
387 * @kref: the reap_ref in the target being released
389 * Called on last put of reap_ref, which is the indication that no device
390 * under this target is visible anymore, so render the target invisible in
391 * sysfs. Note: we have to be in user context here because the target reaps
392 * should be done in places where the scsi device visibility is being removed.
394 static void scsi_target_reap_ref_release(struct kref *kref)
396 struct scsi_target *starget
397 = container_of(kref, struct scsi_target, reap_ref);
399 transport_remove_device(&starget->dev);
400 device_del(&starget->dev);
401 starget->state = STARGET_DEL;
402 scsi_target_destroy(starget);
405 static void scsi_target_reap_ref_put(struct scsi_target *starget)
407 kref_put(&starget->reap_ref, scsi_target_reap_ref_release);
411 * scsi_alloc_target - allocate a new or find an existing target
412 * @parent: parent of the target (need not be a scsi host)
413 * @channel: target channel number (zero if no channels)
414 * @id: target id number
416 * Return an existing target if one exists, provided it hasn't already
417 * gone into STARGET_DEL state, otherwise allocate a new target.
419 * The target is returned with an incremented reference, so the caller
420 * is responsible for both reaping and doing a last put
422 static struct scsi_target *scsi_alloc_target(struct device *parent,
423 int channel, uint id)
425 struct Scsi_Host *shost = dev_to_shost(parent);
426 struct device *dev = NULL;
428 const int size = sizeof(struct scsi_target)
429 + shost->transportt->target_size;
430 struct scsi_target *starget;
431 struct scsi_target *found_target;
434 starget = kzalloc(size, GFP_KERNEL);
436 printk(KERN_ERR "%s: allocation failure\n", __func__);
440 device_initialize(dev);
441 kref_init(&starget->reap_ref);
442 dev->parent = get_device(parent);
443 dev_set_name(dev, "target%d:%d:%d", shost->host_no, channel, id);
444 dev->bus = &scsi_bus_type;
445 dev->type = &scsi_target_type;
447 starget->channel = channel;
448 starget->can_queue = 0;
449 INIT_LIST_HEAD(&starget->siblings);
450 INIT_LIST_HEAD(&starget->devices);
451 starget->state = STARGET_CREATED;
452 starget->scsi_level = SCSI_2;
453 starget->max_target_blocked = SCSI_DEFAULT_TARGET_BLOCKED;
455 spin_lock_irqsave(shost->host_lock, flags);
457 found_target = __scsi_find_target(parent, channel, id);
461 list_add_tail(&starget->siblings, &shost->__targets);
462 spin_unlock_irqrestore(shost->host_lock, flags);
463 /* allocate and add */
464 transport_setup_device(dev);
465 if (shost->hostt->target_alloc) {
466 error = shost->hostt->target_alloc(starget);
469 dev_printk(KERN_ERR, dev, "target allocation failed, error %d\n", error);
470 /* don't want scsi_target_reap to do the final
471 * put because it will be under the host lock */
472 scsi_target_destroy(starget);
482 * release routine already fired if kref is zero, so if we can still
483 * take the reference, the target must be alive. If we can't, it must
484 * be dying and we need to wait for a new target
486 ref_got = kref_get_unless_zero(&found_target->reap_ref);
488 spin_unlock_irqrestore(shost->host_lock, flags);
494 * Unfortunately, we found a dying target; need to wait until it's
495 * dead before we can get a new one. There is an anomaly here. We
496 * *should* call scsi_target_reap() to balance the kref_get() of the
497 * reap_ref above. However, since the target being released, it's
498 * already invisible and the reap_ref is irrelevant. If we call
499 * scsi_target_reap() we might spuriously do another device_del() on
500 * an already invisible target.
502 put_device(&found_target->dev);
504 * length of time is irrelevant here, we just want to yield the CPU
505 * for a tick to avoid busy waiting for the target to die.
512 * scsi_target_reap - check to see if target is in use and destroy if not
513 * @starget: target to be checked
515 * This is used after removing a LUN or doing a last put of the target
516 * it checks atomically that nothing is using the target and removes
519 void scsi_target_reap(struct scsi_target *starget)
521 BUG_ON(starget->state == STARGET_DEL);
522 if (starget->state == STARGET_CREATED)
523 scsi_target_destroy(starget);
525 scsi_target_reap_ref_put(starget);
529 * sanitize_inquiry_string - remove non-graphical chars from an INQUIRY result string
530 * @s: INQUIRY result string to sanitize
531 * @len: length of the string
534 * The SCSI spec says that INQUIRY vendor, product, and revision
535 * strings must consist entirely of graphic ASCII characters,
536 * padded on the right with spaces. Since not all devices obey
537 * this rule, we will replace non-graphic or non-ASCII characters
538 * with spaces. Exception: a NUL character is interpreted as a
539 * string terminator, so all the following characters are set to
542 static void sanitize_inquiry_string(unsigned char *s, int len)
546 for (; len > 0; (--len, ++s)) {
549 if (terminated || *s < 0x20 || *s > 0x7e)
555 * scsi_probe_lun - probe a single LUN using a SCSI INQUIRY
556 * @sdev: scsi_device to probe
557 * @inq_result: area to store the INQUIRY result
558 * @result_len: len of inq_result
559 * @bflags: store any bflags found here
562 * Probe the lun associated with @req using a standard SCSI INQUIRY;
564 * If the INQUIRY is successful, zero is returned and the
565 * INQUIRY data is in @inq_result; the scsi_level and INQUIRY length
566 * are copied to the scsi_device any flags value is stored in *@bflags.
568 static int scsi_probe_lun(struct scsi_device *sdev, unsigned char *inq_result,
569 int result_len, int *bflags)
571 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
572 int first_inquiry_len, try_inquiry_len, next_inquiry_len;
573 int response_len = 0;
574 int pass, count, result;
575 struct scsi_sense_hdr sshdr;
579 /* Perform up to 3 passes. The first pass uses a conservative
580 * transfer length of 36 unless sdev->inquiry_len specifies a
581 * different value. */
582 first_inquiry_len = sdev->inquiry_len ? sdev->inquiry_len : 36;
583 try_inquiry_len = first_inquiry_len;
587 SCSI_LOG_SCAN_BUS(3, sdev_printk(KERN_INFO, sdev,
588 "scsi scan: INQUIRY pass %d length %d\n",
589 pass, try_inquiry_len));
591 /* Each pass gets up to three chances to ignore Unit Attention */
592 for (count = 0; count < 3; ++count) {
595 memset(scsi_cmd, 0, 6);
596 scsi_cmd[0] = INQUIRY;
597 scsi_cmd[4] = (unsigned char) try_inquiry_len;
599 memset(inq_result, 0, try_inquiry_len);
601 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
602 inq_result, try_inquiry_len, &sshdr,
603 HZ / 2 + HZ * scsi_inq_timeout, 3,
606 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY %s "
608 result ? "failed" : "successful", result));
612 * not-ready to ready transition [asc/ascq=0x28/0x0]
613 * or power-on, reset [asc/ascq=0x29/0x0], continue.
614 * INQUIRY should not yield UNIT_ATTENTION
615 * but many buggy devices do so anyway.
617 if ((driver_byte(result) & DRIVER_SENSE) &&
618 scsi_sense_valid(&sshdr)) {
619 if ((sshdr.sense_key == UNIT_ATTENTION) &&
620 ((sshdr.asc == 0x28) ||
621 (sshdr.asc == 0x29)) &&
627 * if nothing was transferred, we try
628 * again. It's a workaround for some USB
631 if (resid == try_inquiry_len)
638 sanitize_inquiry_string(&inq_result[8], 8);
639 sanitize_inquiry_string(&inq_result[16], 16);
640 sanitize_inquiry_string(&inq_result[32], 4);
642 response_len = inq_result[4] + 5;
643 if (response_len > 255)
644 response_len = first_inquiry_len; /* sanity */
647 * Get any flags for this device.
649 * XXX add a bflags to scsi_device, and replace the
650 * corresponding bit fields in scsi_device, so bflags
651 * need not be passed as an argument.
653 *bflags = scsi_get_device_flags(sdev, &inq_result[8],
656 /* When the first pass succeeds we gain information about
657 * what larger transfer lengths might work. */
659 if (BLIST_INQUIRY_36 & *bflags)
660 next_inquiry_len = 36;
661 else if (BLIST_INQUIRY_58 & *bflags)
662 next_inquiry_len = 58;
663 else if (sdev->inquiry_len)
664 next_inquiry_len = sdev->inquiry_len;
666 next_inquiry_len = response_len;
668 /* If more data is available perform the second pass */
669 if (next_inquiry_len > try_inquiry_len) {
670 try_inquiry_len = next_inquiry_len;
676 } else if (pass == 2) {
677 printk(KERN_INFO "scsi scan: %d byte inquiry failed. "
678 "Consider BLIST_INQUIRY_36 for this device\n",
681 /* If this pass failed, the third pass goes back and transfers
682 * the same amount as we successfully got in the first pass. */
683 try_inquiry_len = first_inquiry_len;
688 /* If the last transfer attempt got an error, assume the
689 * peripheral doesn't exist or is dead. */
693 /* Don't report any more data than the device says is valid */
694 sdev->inquiry_len = min(try_inquiry_len, response_len);
697 * XXX Abort if the response length is less than 36? If less than
698 * 32, the lookup of the device flags (above) could be invalid,
699 * and it would be possible to take an incorrect action - we do
700 * not want to hang because of a short INQUIRY. On the flip side,
701 * if the device is spun down or becoming ready (and so it gives a
702 * short INQUIRY), an abort here prevents any further use of the
703 * device, including spin up.
705 * On the whole, the best approach seems to be to assume the first
706 * 36 bytes are valid no matter what the device says. That's
707 * better than copying < 36 bytes to the inquiry-result buffer
708 * and displaying garbage for the Vendor, Product, or Revision
711 if (sdev->inquiry_len < 36) {
712 printk(KERN_INFO "scsi scan: INQUIRY result too short (%d),"
713 " using 36\n", sdev->inquiry_len);
714 sdev->inquiry_len = 36;
718 * Related to the above issue:
720 * XXX Devices (disk or all?) should be sent a TEST UNIT READY,
721 * and if not ready, sent a START_STOP to start (maybe spin up) and
722 * then send the INQUIRY again, since the INQUIRY can change after
723 * a device is initialized.
725 * Ideally, start a device if explicitly asked to do so. This
726 * assumes that a device is spun up on power on, spun down on
727 * request, and then spun up on request.
731 * The scanning code needs to know the scsi_level, even if no
732 * device is attached at LUN 0 (SCSI_SCAN_TARGET_PRESENT) so
733 * non-zero LUNs can be scanned.
735 sdev->scsi_level = inq_result[2] & 0x07;
736 if (sdev->scsi_level >= 2 ||
737 (sdev->scsi_level == 1 && (inq_result[3] & 0x0f) == 1))
739 sdev->sdev_target->scsi_level = sdev->scsi_level;
745 * scsi_add_lun - allocate and fully initialze a scsi_device
746 * @sdev: holds information to be stored in the new scsi_device
747 * @inq_result: holds the result of a previous INQUIRY to the LUN
748 * @bflags: black/white list flag
749 * @async: 1 if this device is being scanned asynchronously
752 * Initialize the scsi_device @sdev. Optionally set fields based
753 * on values in *@bflags.
756 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
757 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
759 static int scsi_add_lun(struct scsi_device *sdev, unsigned char *inq_result,
760 int *bflags, int async)
765 * XXX do not save the inquiry, since it can change underneath us,
766 * save just vendor/model/rev.
768 * Rather than save it and have an ioctl that retrieves the saved
769 * value, have an ioctl that executes the same INQUIRY code used
770 * in scsi_probe_lun, let user level programs doing INQUIRY
771 * scanning run at their own risk, or supply a user level program
772 * that can correctly scan.
776 * Copy at least 36 bytes of INQUIRY data, so that we don't
777 * dereference unallocated memory when accessing the Vendor,
778 * Product, and Revision strings. Badly behaved devices may set
779 * the INQUIRY Additional Length byte to a small value, indicating
780 * these strings are invalid, but often they contain plausible data
781 * nonetheless. It doesn't matter if the device sent < 36 bytes
782 * total, since scsi_probe_lun() initializes inq_result with 0s.
784 sdev->inquiry = kmemdup(inq_result,
785 max_t(size_t, sdev->inquiry_len, 36),
787 if (sdev->inquiry == NULL)
788 return SCSI_SCAN_NO_RESPONSE;
790 sdev->vendor = (char *) (sdev->inquiry + 8);
791 sdev->model = (char *) (sdev->inquiry + 16);
792 sdev->rev = (char *) (sdev->inquiry + 32);
794 if (strncmp(sdev->vendor, "ATA ", 8) == 0) {
796 * sata emulation layer device. This is a hack to work around
797 * the SATL power management specifications which state that
798 * when the SATL detects the device has gone into standby
799 * mode, it shall respond with NOT READY.
801 sdev->allow_restart = 1;
804 if (*bflags & BLIST_ISROM) {
805 sdev->type = TYPE_ROM;
808 sdev->type = (inq_result[0] & 0x1f);
809 sdev->removable = (inq_result[1] & 0x80) >> 7;
812 switch (sdev->type) {
820 case TYPE_MEDIUM_CHANGER:
832 printk(KERN_INFO "scsi: unknown device type %d\n", sdev->type);
835 if (sdev->type == TYPE_RBC || sdev->type == TYPE_ROM) {
836 /* RBC and MMC devices can return SCSI-3 compliance and yet
837 * still not support REPORT LUNS, so make them act as
838 * BLIST_NOREPORTLUN unless BLIST_REPORTLUN2 is
839 * specifically set */
840 if ((*bflags & BLIST_REPORTLUN2) == 0)
841 *bflags |= BLIST_NOREPORTLUN;
845 * For a peripheral qualifier (PQ) value of 1 (001b), the SCSI
846 * spec says: The device server is capable of supporting the
847 * specified peripheral device type on this logical unit. However,
848 * the physical device is not currently connected to this logical
851 * The above is vague, as it implies that we could treat 001 and
852 * 011 the same. Stay compatible with previous code, and create a
853 * scsi_device for a PQ of 1
855 * Don't set the device offline here; rather let the upper
856 * level drivers eval the PQ to decide whether they should
857 * attach. So remove ((inq_result[0] >> 5) & 7) == 1 check.
860 sdev->inq_periph_qual = (inq_result[0] >> 5) & 7;
861 sdev->lockable = sdev->removable;
862 sdev->soft_reset = (inq_result[7] & 1) && ((inq_result[3] & 7) == 2);
864 if (sdev->scsi_level >= SCSI_3 ||
865 (sdev->inquiry_len > 56 && inq_result[56] & 0x04))
867 if (inq_result[7] & 0x60)
869 if (inq_result[7] & 0x10)
872 sdev_printk(KERN_NOTICE, sdev, "%s %.8s %.16s %.4s PQ: %d "
873 "ANSI: %d%s\n", scsi_device_type(sdev->type),
874 sdev->vendor, sdev->model, sdev->rev,
875 sdev->inq_periph_qual, inq_result[2] & 0x07,
876 (inq_result[3] & 0x0f) == 1 ? " CCS" : "");
878 if ((sdev->scsi_level >= SCSI_2) && (inq_result[7] & 2) &&
879 !(*bflags & BLIST_NOTQ))
880 sdev->tagged_supported = 1;
883 * Some devices (Texel CD ROM drives) have handshaking problems
884 * when used with the Seagate controllers. borken is initialized
885 * to 1, and then set it to 0 here.
887 if ((*bflags & BLIST_BORKEN) == 0)
890 if (*bflags & BLIST_NO_ULD_ATTACH)
891 sdev->no_uld_attach = 1;
894 * Apparently some really broken devices (contrary to the SCSI
895 * standards) need to be selected without asserting ATN
897 if (*bflags & BLIST_SELECT_NO_ATN)
898 sdev->select_no_atn = 1;
901 * Maximum 512 sector transfer length
902 * broken RA4x00 Compaq Disk Array
904 if (*bflags & BLIST_MAX_512)
905 blk_queue_max_hw_sectors(sdev->request_queue, 512);
908 * Some devices may not want to have a start command automatically
909 * issued when a device is added.
911 if (*bflags & BLIST_NOSTARTONADD)
912 sdev->no_start_on_add = 1;
914 if (*bflags & BLIST_SINGLELUN)
915 scsi_target(sdev)->single_lun = 1;
917 sdev->use_10_for_rw = 1;
919 if (*bflags & BLIST_MS_SKIP_PAGE_08)
920 sdev->skip_ms_page_8 = 1;
922 if (*bflags & BLIST_MS_SKIP_PAGE_3F)
923 sdev->skip_ms_page_3f = 1;
925 if (*bflags & BLIST_USE_10_BYTE_MS)
926 sdev->use_10_for_ms = 1;
928 /* set the device running here so that slave configure
930 ret = scsi_device_set_state(sdev, SDEV_RUNNING);
932 ret = scsi_device_set_state(sdev, SDEV_BLOCK);
935 sdev_printk(KERN_ERR, sdev,
936 "in wrong state %s to complete scan\n",
937 scsi_device_state_name(sdev->sdev_state));
938 return SCSI_SCAN_NO_RESPONSE;
942 if (*bflags & BLIST_MS_192_BYTES_FOR_3F)
943 sdev->use_192_bytes_for_3f = 1;
945 if (*bflags & BLIST_NOT_LOCKABLE)
948 if (*bflags & BLIST_RETRY_HWERROR)
949 sdev->retry_hwerror = 1;
951 transport_configure_device(&sdev->sdev_gendev);
953 if (sdev->host->hostt->slave_configure) {
954 ret = sdev->host->hostt->slave_configure(sdev);
957 * if LLDD reports slave not present, don't clutter
958 * console with alloc failure messages
961 sdev_printk(KERN_ERR, sdev,
962 "failed to configure device\n");
964 return SCSI_SCAN_NO_RESPONSE;
968 sdev->max_queue_depth = sdev->queue_depth;
971 * Ok, the device is now all set up, we can
972 * register it and tell the rest of the kernel
975 if (!async && scsi_sysfs_add_sdev(sdev) != 0)
976 return SCSI_SCAN_NO_RESPONSE;
978 return SCSI_SCAN_LUN_PRESENT;
981 #ifdef CONFIG_SCSI_LOGGING
983 * scsi_inq_str - print INQUIRY data from min to max index, strip trailing whitespace
984 * @buf: Output buffer with at least end-first+1 bytes of space
985 * @inq: Inquiry buffer (input)
986 * @first: Offset of string into inq
987 * @end: Index after last character in inq
989 static unsigned char *scsi_inq_str(unsigned char *buf, unsigned char *inq,
990 unsigned first, unsigned end)
992 unsigned term = 0, idx;
994 for (idx = 0; idx + first < end && idx + first < inq[4] + 5; idx++) {
995 if (inq[idx+first] > ' ') {
996 buf[idx] = inq[idx+first];
1008 * scsi_probe_and_add_lun - probe a LUN, if a LUN is found add it
1009 * @starget: pointer to target device structure
1010 * @lun: LUN of target device
1011 * @bflagsp: store bflags here if not NULL
1012 * @sdevp: probe the LUN corresponding to this scsi_device
1013 * @rescan: if nonzero skip some code only needed on first scan
1014 * @hostdata: passed to scsi_alloc_sdev()
1017 * Call scsi_probe_lun, if a LUN with an attached device is found,
1018 * allocate and set it up by calling scsi_add_lun.
1021 * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a scsi_device
1022 * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
1023 * attached at the LUN
1024 * SCSI_SCAN_LUN_PRESENT: a new scsi_device was allocated and initialized
1026 static int scsi_probe_and_add_lun(struct scsi_target *starget,
1027 uint lun, int *bflagsp,
1028 struct scsi_device **sdevp, int rescan,
1031 struct scsi_device *sdev;
1032 unsigned char *result;
1033 int bflags, res = SCSI_SCAN_NO_RESPONSE, result_len = 256;
1034 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1037 * The rescan flag is used as an optimization, the first scan of a
1038 * host adapter calls into here with rescan == 0.
1040 sdev = scsi_device_lookup_by_target(starget, lun);
1042 if (rescan || !scsi_device_created(sdev)) {
1043 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1044 "scsi scan: device exists on %s\n",
1045 dev_name(&sdev->sdev_gendev)));
1049 scsi_device_put(sdev);
1052 *bflagsp = scsi_get_device_flags(sdev,
1055 return SCSI_SCAN_LUN_PRESENT;
1057 scsi_device_put(sdev);
1059 sdev = scsi_alloc_sdev(starget, lun, hostdata);
1063 result = kmalloc(result_len, GFP_ATOMIC |
1064 ((shost->unchecked_isa_dma) ? __GFP_DMA : 0));
1068 if (scsi_probe_lun(sdev, result, result_len, &bflags))
1069 goto out_free_result;
1074 * result contains valid SCSI INQUIRY data.
1076 if (((result[0] >> 5) == 3) && !(bflags & BLIST_ATTACH_PQ3)) {
1078 * For a Peripheral qualifier 3 (011b), the SCSI
1079 * spec says: The device server is not capable of
1080 * supporting a physical device on this logical
1083 * For disks, this implies that there is no
1084 * logical disk configured at sdev->lun, but there
1085 * is a target id responding.
1087 SCSI_LOG_SCAN_BUS(2, sdev_printk(KERN_INFO, sdev, "scsi scan:"
1088 " peripheral qualifier of 3, device not"
1091 SCSI_LOG_SCAN_BUS(1, {
1092 unsigned char vend[9];
1093 unsigned char mod[17];
1095 sdev_printk(KERN_INFO, sdev,
1096 "scsi scan: consider passing scsi_mod."
1097 "dev_flags=%s:%s:0x240 or 0x1000240\n",
1098 scsi_inq_str(vend, result, 8, 16),
1099 scsi_inq_str(mod, result, 16, 32));
1104 res = SCSI_SCAN_TARGET_PRESENT;
1105 goto out_free_result;
1109 * Some targets may set slight variations of PQ and PDT to signal
1110 * that no LUN is present, so don't add sdev in these cases.
1111 * Two specific examples are:
1112 * 1) NetApp targets: return PQ=1, PDT=0x1f
1113 * 2) USB UFI: returns PDT=0x1f, with the PQ bits being "reserved"
1114 * in the UFI 1.0 spec (we cannot rely on reserved bits).
1117 * 1) SCSI SPC-3, pp. 145-146
1118 * PQ=1: "A peripheral device having the specified peripheral
1119 * device type is not connected to this logical unit. However, the
1120 * device server is capable of supporting the specified peripheral
1121 * device type on this logical unit."
1122 * PDT=0x1f: "Unknown or no device type"
1123 * 2) USB UFI 1.0, p. 20
1124 * PDT=00h Direct-access device (floppy)
1125 * PDT=1Fh none (no FDD connected to the requested logical unit)
1127 if (((result[0] >> 5) == 1 || starget->pdt_1f_for_no_lun) &&
1128 (result[0] & 0x1f) == 0x1f &&
1129 !scsi_is_wlun(lun)) {
1130 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO
1131 "scsi scan: peripheral device type"
1132 " of 31, no device added\n"));
1133 res = SCSI_SCAN_TARGET_PRESENT;
1134 goto out_free_result;
1137 res = scsi_add_lun(sdev, result, &bflags, shost->async_scan);
1138 if (res == SCSI_SCAN_LUN_PRESENT) {
1139 if (bflags & BLIST_KEY) {
1141 scsi_unlock_floptical(sdev, result);
1148 if (res == SCSI_SCAN_LUN_PRESENT) {
1150 if (scsi_device_get(sdev) == 0) {
1153 __scsi_remove_device(sdev);
1154 res = SCSI_SCAN_NO_RESPONSE;
1158 __scsi_remove_device(sdev);
1164 * scsi_sequential_lun_scan - sequentially scan a SCSI target
1165 * @starget: pointer to target structure to scan
1166 * @bflags: black/white list flag for LUN 0
1167 * @scsi_level: Which version of the standard does this device adhere to
1168 * @rescan: passed to scsi_probe_add_lun()
1171 * Generally, scan from LUN 1 (LUN 0 is assumed to already have been
1172 * scanned) to some maximum lun until a LUN is found with no device
1173 * attached. Use the bflags to figure out any oddities.
1175 * Modifies sdevscan->lun.
1177 static void scsi_sequential_lun_scan(struct scsi_target *starget,
1178 int bflags, int scsi_level, int rescan)
1180 unsigned int sparse_lun, lun, max_dev_lun;
1181 struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
1183 SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
1184 "%s\n", dev_name(&starget->dev)));
1186 max_dev_lun = min(max_scsi_luns, shost->max_lun);
1188 * If this device is known to support sparse multiple units,
1189 * override the other settings, and scan all of them. Normally,
1190 * SCSI-3 devices should be scanned via the REPORT LUNS.
1192 if (bflags & BLIST_SPARSELUN) {
1193 max_dev_lun = shost->max_lun;
1199 * If less than SCSI_1_CSS, and no special lun scaning, stop
1200 * scanning; this matches 2.4 behaviour, but could just be a bug
1201 * (to continue scanning a SCSI_1_CSS device).
1203 * This test is broken. We might not have any device on lun0 for
1204 * a sparselun device, and if that's the case then how would we
1205 * know the real scsi_level, eh? It might make sense to just not
1206 * scan any SCSI_1 device for non-0 luns, but that check would best
1207 * go into scsi_alloc_sdev() and just have it return null when asked
1208 * to alloc an sdev for lun > 0 on an already found SCSI_1 device.
1210 if ((sdevscan->scsi_level < SCSI_1_CCS) &&
1211 ((bflags & (BLIST_FORCELUN | BLIST_SPARSELUN | BLIST_MAX5LUN))
1216 * If this device is known to support multiple units, override
1217 * the other settings, and scan all of them.
1219 if (bflags & BLIST_FORCELUN)
1220 max_dev_lun = shost->max_lun;
1222 * REGAL CDC-4X: avoid hang after LUN 4
1224 if (bflags & BLIST_MAX5LUN)
1225 max_dev_lun = min(5U, max_dev_lun);
1227 * Do not scan SCSI-2 or lower device past LUN 7, unless
1230 if (scsi_level < SCSI_3 && !(bflags & BLIST_LARGELUN))
1231 max_dev_lun = min(8U, max_dev_lun);
1234 * We have already scanned LUN 0, so start at LUN 1. Keep scanning
1235 * until we reach the max, or no LUN is found and we are not
1238 for (lun = 1; lun < max_dev_lun; ++lun)
1239 if ((scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan,
1240 NULL) != SCSI_SCAN_LUN_PRESENT) &&
1246 * scsilun_to_int - convert a scsi_lun to an int
1247 * @scsilun: struct scsi_lun to be converted.
1250 * Convert @scsilun from a struct scsi_lun to a four byte host byte-ordered
1251 * integer, and return the result. The caller must check for
1252 * truncation before using this function.
1255 * The struct scsi_lun is assumed to be four levels, with each level
1256 * effectively containing a SCSI byte-ordered (big endian) short; the
1257 * addressing bits of each level are ignored (the highest two bits).
1258 * For a description of the LUN format, post SCSI-3 see the SCSI
1259 * Architecture Model, for SCSI-3 see the SCSI Controller Commands.
1261 * Given a struct scsi_lun of: 0a 04 0b 03 00 00 00 00, this function returns
1262 * the integer: 0x0b030a04
1264 int scsilun_to_int(struct scsi_lun *scsilun)
1270 for (i = 0; i < sizeof(lun); i += 2)
1271 lun = lun | (((scsilun->scsi_lun[i] << 8) |
1272 scsilun->scsi_lun[i + 1]) << (i * 8));
1275 EXPORT_SYMBOL(scsilun_to_int);
1278 * int_to_scsilun - reverts an int into a scsi_lun
1279 * @lun: integer to be reverted
1280 * @scsilun: struct scsi_lun to be set.
1283 * Reverts the functionality of the scsilun_to_int, which packed
1284 * an 8-byte lun value into an int. This routine unpacks the int
1285 * back into the lun value.
1286 * Note: the scsilun_to_int() routine does not truly handle all
1287 * 8bytes of the lun value. This functions restores only as much
1288 * as was set by the routine.
1291 * Given an integer : 0x0b030a04, this function returns a
1292 * scsi_lun of : struct scsi_lun of: 0a 04 0b 03 00 00 00 00
1295 void int_to_scsilun(unsigned int lun, struct scsi_lun *scsilun)
1299 memset(scsilun->scsi_lun, 0, sizeof(scsilun->scsi_lun));
1301 for (i = 0; i < sizeof(lun); i += 2) {
1302 scsilun->scsi_lun[i] = (lun >> 8) & 0xFF;
1303 scsilun->scsi_lun[i+1] = lun & 0xFF;
1307 EXPORT_SYMBOL(int_to_scsilun);
1310 * scsi_report_lun_scan - Scan using SCSI REPORT LUN results
1311 * @starget: which target
1312 * @bflags: Zero or a mix of BLIST_NOLUN, BLIST_REPORTLUN2, or BLIST_NOREPORTLUN
1313 * @rescan: nonzero if we can skip code only needed on first scan
1316 * Fast scanning for modern (SCSI-3) devices by sending a REPORT LUN command.
1317 * Scan the resulting list of LUNs by calling scsi_probe_and_add_lun.
1319 * If BLINK_REPORTLUN2 is set, scan a target that supports more than 8
1320 * LUNs even if it's older than SCSI-3.
1321 * If BLIST_NOREPORTLUN is set, return 1 always.
1322 * If BLIST_NOLUN is set, return 0 always.
1325 * 0: scan completed (or no memory, so further scanning is futile)
1326 * 1: could not scan with REPORT LUN
1328 static int scsi_report_lun_scan(struct scsi_target *starget, int bflags,
1332 unsigned char scsi_cmd[MAX_COMMAND_SIZE];
1333 unsigned int length;
1335 unsigned int num_luns;
1336 unsigned int retries;
1338 struct scsi_lun *lunp, *lun_data;
1340 struct scsi_sense_hdr sshdr;
1341 struct scsi_device *sdev;
1342 struct Scsi_Host *shost = dev_to_shost(&starget->dev);
1346 * Only support SCSI-3 and up devices if BLIST_NOREPORTLUN is not set.
1347 * Also allow SCSI-2 if BLIST_REPORTLUN2 is set and host adapter does
1348 * support more than 8 LUNs.
1350 if (bflags & BLIST_NOREPORTLUN)
1352 if (starget->scsi_level < SCSI_2 &&
1353 starget->scsi_level != SCSI_UNKNOWN)
1355 if (starget->scsi_level < SCSI_3 &&
1356 (!(bflags & BLIST_REPORTLUN2) || shost->max_lun <= 8))
1358 if (bflags & BLIST_NOLUN)
1361 if (!(sdev = scsi_device_lookup_by_target(starget, 0))) {
1362 sdev = scsi_alloc_sdev(starget, 0, NULL);
1365 if (scsi_device_get(sdev)) {
1366 __scsi_remove_device(sdev);
1371 sprintf(devname, "host %d channel %d id %d",
1372 shost->host_no, sdev->channel, sdev->id);
1375 * Allocate enough to hold the header (the same size as one scsi_lun)
1376 * plus the max number of luns we are requesting.
1378 * Reallocating and trying again (with the exact amount we need)
1379 * would be nice, but then we need to somehow limit the size
1380 * allocated based on the available memory and the limits of
1381 * kmalloc - we don't want a kmalloc() failure of a huge value to
1382 * prevent us from finding any LUNs on this target.
1384 length = (max_scsi_report_luns + 1) * sizeof(struct scsi_lun);
1385 lun_data = kmalloc(length, GFP_ATOMIC |
1386 (sdev->host->unchecked_isa_dma ? __GFP_DMA : 0));
1388 printk(ALLOC_FAILURE_MSG, __func__);
1392 scsi_cmd[0] = REPORT_LUNS;
1395 * bytes 1 - 5: reserved, set to zero.
1397 memset(&scsi_cmd[1], 0, 5);
1400 * bytes 6 - 9: length of the command.
1402 scsi_cmd[6] = (unsigned char) (length >> 24) & 0xff;
1403 scsi_cmd[7] = (unsigned char) (length >> 16) & 0xff;
1404 scsi_cmd[8] = (unsigned char) (length >> 8) & 0xff;
1405 scsi_cmd[9] = (unsigned char) length & 0xff;
1407 scsi_cmd[10] = 0; /* reserved */
1408 scsi_cmd[11] = 0; /* control */
1411 * We can get a UNIT ATTENTION, for example a power on/reset, so
1412 * retry a few times (like sd.c does for TEST UNIT READY).
1413 * Experience shows some combinations of adapter/devices get at
1414 * least two power on/resets.
1416 * Illegal requests (for devices that do not support REPORT LUNS)
1417 * should come through as a check condition, and will not generate
1420 for (retries = 0; retries < 3; retries++) {
1421 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: Sending"
1422 " REPORT LUNS to %s (try %d)\n", devname,
1425 result = scsi_execute_req(sdev, scsi_cmd, DMA_FROM_DEVICE,
1426 lun_data, length, &sshdr,
1427 SCSI_TIMEOUT + 4 * HZ, 3, NULL);
1429 SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUNS"
1430 " %s (try %d) result 0x%x\n", result
1431 ? "failed" : "successful", retries, result));
1434 else if (scsi_sense_valid(&sshdr)) {
1435 if (sshdr.sense_key != UNIT_ATTENTION)
1442 * The device probably does not support a REPORT LUN command
1449 * Get the length from the first four bytes of lun_data.
1451 data = (u8 *) lun_data->scsi_lun;
1452 length = ((data[0] << 24) | (data[1] << 16) |
1453 (data[2] << 8) | (data[3] << 0));
1455 num_luns = (length / sizeof(struct scsi_lun));
1456 if (num_luns > max_scsi_report_luns) {
1457 printk(KERN_WARNING "scsi: On %s only %d (max_scsi_report_luns)"
1458 " of %d luns reported, try increasing"
1459 " max_scsi_report_luns.\n", devname,
1460 max_scsi_report_luns, num_luns);
1461 num_luns = max_scsi_report_luns;
1464 SCSI_LOG_SCAN_BUS(3, sdev_printk (KERN_INFO, sdev,
1465 "scsi scan: REPORT LUN scan\n"));
1468 * Scan the luns in lun_data. The entry at offset 0 is really
1469 * the header, so start at 1 and go up to and including num_luns.
1471 for (lunp = &lun_data[1]; lunp <= &lun_data[num_luns]; lunp++) {
1472 lun = scsilun_to_int(lunp);
1475 * Check if the unused part of lunp is non-zero, and so
1476 * does not fit in lun.
1478 if (memcmp(&lunp->scsi_lun[sizeof(lun)], "\0\0\0\0", 4)) {
1482 * Output an error displaying the LUN in byte order,
1483 * this differs from what linux would print for the
1484 * integer LUN value.
1486 printk(KERN_WARNING "scsi: %s lun 0x", devname);
1487 data = (char *)lunp->scsi_lun;
1488 for (i = 0; i < sizeof(struct scsi_lun); i++)
1489 printk("%02x", data[i]);
1490 printk(" has a LUN larger than currently supported.\n");
1491 } else if (lun > sdev->host->max_lun) {
1492 printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
1493 " than allowed by the host adapter\n",
1498 res = scsi_probe_and_add_lun(starget,
1499 lun, NULL, NULL, rescan, NULL);
1500 if (res == SCSI_SCAN_NO_RESPONSE) {
1502 * Got some results, but now none, abort.
1504 sdev_printk(KERN_ERR, sdev,
1505 "Unexpected response"
1506 " from lun %d while scanning, scan"
1516 scsi_device_put(sdev);
1517 if (scsi_device_created(sdev))
1519 * the sdev we used didn't appear in the report luns scan
1521 __scsi_remove_device(sdev);
1525 struct scsi_device *__scsi_add_device(struct Scsi_Host *shost, uint channel,
1526 uint id, uint lun, void *hostdata)
1528 struct scsi_device *sdev = ERR_PTR(-ENODEV);
1529 struct device *parent = &shost->shost_gendev;
1530 struct scsi_target *starget;
1532 if (strncmp(scsi_scan_type, "none", 4) == 0)
1533 return ERR_PTR(-ENODEV);
1535 starget = scsi_alloc_target(parent, channel, id);
1537 return ERR_PTR(-ENOMEM);
1538 scsi_autopm_get_target(starget);
1540 mutex_lock(&shost->scan_mutex);
1541 if (!shost->async_scan)
1542 scsi_complete_async_scans();
1544 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1545 scsi_probe_and_add_lun(starget, lun, NULL, &sdev, 1, hostdata);
1546 scsi_autopm_put_host(shost);
1548 mutex_unlock(&shost->scan_mutex);
1549 scsi_autopm_put_target(starget);
1551 * paired with scsi_alloc_target(). Target will be destroyed unless
1552 * scsi_probe_and_add_lun made an underlying device visible
1554 scsi_target_reap(starget);
1555 put_device(&starget->dev);
1559 EXPORT_SYMBOL(__scsi_add_device);
1561 int scsi_add_device(struct Scsi_Host *host, uint channel,
1562 uint target, uint lun)
1564 struct scsi_device *sdev =
1565 __scsi_add_device(host, channel, target, lun, NULL);
1567 return PTR_ERR(sdev);
1569 scsi_device_put(sdev);
1572 EXPORT_SYMBOL(scsi_add_device);
1574 void scsi_rescan_device(struct device *dev)
1576 struct scsi_driver *drv;
1581 drv = to_scsi_driver(dev->driver);
1582 if (try_module_get(drv->owner)) {
1585 module_put(drv->owner);
1588 EXPORT_SYMBOL(scsi_rescan_device);
1590 static void __scsi_scan_target(struct device *parent, unsigned int channel,
1591 unsigned int id, unsigned int lun, int rescan)
1593 struct Scsi_Host *shost = dev_to_shost(parent);
1596 struct scsi_target *starget;
1598 if (shost->this_id == id)
1600 * Don't scan the host adapter
1604 starget = scsi_alloc_target(parent, channel, id);
1607 scsi_autopm_get_target(starget);
1609 if (lun != SCAN_WILD_CARD) {
1611 * Scan for a specific host/chan/id/lun.
1613 scsi_probe_and_add_lun(starget, lun, NULL, NULL, rescan, NULL);
1618 * Scan LUN 0, if there is some response, scan further. Ideally, we
1619 * would not configure LUN 0 until all LUNs are scanned.
1621 res = scsi_probe_and_add_lun(starget, 0, &bflags, NULL, rescan, NULL);
1622 if (res == SCSI_SCAN_LUN_PRESENT || res == SCSI_SCAN_TARGET_PRESENT) {
1623 if (scsi_report_lun_scan(starget, bflags, rescan) != 0)
1625 * The REPORT LUN did not scan the target,
1626 * do a sequential scan.
1628 scsi_sequential_lun_scan(starget, bflags,
1629 starget->scsi_level, rescan);
1633 scsi_autopm_put_target(starget);
1635 * paired with scsi_alloc_target(): determine if the target has
1636 * any children at all and if not, nuke it
1638 scsi_target_reap(starget);
1640 put_device(&starget->dev);
1644 * scsi_scan_target - scan a target id, possibly including all LUNs on the target.
1645 * @parent: host to scan
1646 * @channel: channel to scan
1647 * @id: target id to scan
1648 * @lun: Specific LUN to scan or SCAN_WILD_CARD
1649 * @rescan: passed to LUN scanning routines
1652 * Scan the target id on @parent, @channel, and @id. Scan at least LUN 0,
1653 * and possibly all LUNs on the target id.
1655 * First try a REPORT LUN scan, if that does not scan the target, do a
1656 * sequential scan of LUNs on the target id.
1658 void scsi_scan_target(struct device *parent, unsigned int channel,
1659 unsigned int id, unsigned int lun, int rescan)
1661 struct Scsi_Host *shost = dev_to_shost(parent);
1663 if (strncmp(scsi_scan_type, "none", 4) == 0)
1666 mutex_lock(&shost->scan_mutex);
1667 if (!shost->async_scan)
1668 scsi_complete_async_scans();
1670 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1671 __scsi_scan_target(parent, channel, id, lun, rescan);
1672 scsi_autopm_put_host(shost);
1674 mutex_unlock(&shost->scan_mutex);
1676 EXPORT_SYMBOL(scsi_scan_target);
1678 static void scsi_scan_channel(struct Scsi_Host *shost, unsigned int channel,
1679 unsigned int id, unsigned int lun, int rescan)
1683 if (id == SCAN_WILD_CARD)
1684 for (id = 0; id < shost->max_id; ++id) {
1686 * XXX adapter drivers when possible (FCP, iSCSI)
1687 * could modify max_id to match the current max,
1688 * not the absolute max.
1690 * XXX add a shost id iterator, so for example,
1691 * the FC ID can be the same as a target id
1692 * without a huge overhead of sparse id's.
1694 if (shost->reverse_ordering)
1696 * Scan from high to low id.
1698 order_id = shost->max_id - id - 1;
1701 __scsi_scan_target(&shost->shost_gendev, channel,
1702 order_id, lun, rescan);
1705 __scsi_scan_target(&shost->shost_gendev, channel,
1709 int scsi_scan_host_selected(struct Scsi_Host *shost, unsigned int channel,
1710 unsigned int id, unsigned int lun, int rescan)
1712 SCSI_LOG_SCAN_BUS(3, shost_printk (KERN_INFO, shost,
1714 __func__, channel, id, lun));
1716 if (((channel != SCAN_WILD_CARD) && (channel > shost->max_channel)) ||
1717 ((id != SCAN_WILD_CARD) && (id >= shost->max_id)) ||
1718 ((lun != SCAN_WILD_CARD) && (lun > shost->max_lun)))
1721 mutex_lock(&shost->scan_mutex);
1722 if (!shost->async_scan)
1723 scsi_complete_async_scans();
1725 if (scsi_host_scan_allowed(shost) && scsi_autopm_get_host(shost) == 0) {
1726 if (channel == SCAN_WILD_CARD)
1727 for (channel = 0; channel <= shost->max_channel;
1729 scsi_scan_channel(shost, channel, id, lun,
1732 scsi_scan_channel(shost, channel, id, lun, rescan);
1733 scsi_autopm_put_host(shost);
1735 mutex_unlock(&shost->scan_mutex);
1740 static void scsi_sysfs_add_devices(struct Scsi_Host *shost)
1742 struct scsi_device *sdev;
1743 shost_for_each_device(sdev, shost) {
1744 /* target removed before the device could be added */
1745 if (sdev->sdev_state == SDEV_DEL)
1747 if (!scsi_host_scan_allowed(shost) ||
1748 scsi_sysfs_add_sdev(sdev) != 0)
1749 __scsi_remove_device(sdev);
1754 * scsi_prep_async_scan - prepare for an async scan
1755 * @shost: the host which will be scanned
1756 * Returns: a cookie to be passed to scsi_finish_async_scan()
1758 * Tells the midlayer this host is going to do an asynchronous scan.
1759 * It reserves the host's position in the scanning list and ensures
1760 * that other asynchronous scans started after this one won't affect the
1761 * ordering of the discovered devices.
1763 static struct async_scan_data *scsi_prep_async_scan(struct Scsi_Host *shost)
1765 struct async_scan_data *data;
1766 unsigned long flags;
1768 if (strncmp(scsi_scan_type, "sync", 4) == 0)
1771 if (shost->async_scan) {
1772 printk("%s called twice for host %d", __func__,
1778 data = kmalloc(sizeof(*data), GFP_KERNEL);
1781 data->shost = scsi_host_get(shost);
1784 init_completion(&data->prev_finished);
1786 mutex_lock(&shost->scan_mutex);
1787 spin_lock_irqsave(shost->host_lock, flags);
1788 shost->async_scan = 1;
1789 spin_unlock_irqrestore(shost->host_lock, flags);
1790 mutex_unlock(&shost->scan_mutex);
1792 spin_lock(&async_scan_lock);
1793 if (list_empty(&scanning_hosts))
1794 complete(&data->prev_finished);
1795 list_add_tail(&data->list, &scanning_hosts);
1796 spin_unlock(&async_scan_lock);
1806 * scsi_finish_async_scan - asynchronous scan has finished
1807 * @data: cookie returned from earlier call to scsi_prep_async_scan()
1809 * All the devices currently attached to this host have been found.
1810 * This function announces all the devices it has found to the rest
1813 static void scsi_finish_async_scan(struct async_scan_data *data)
1815 struct Scsi_Host *shost;
1816 unsigned long flags;
1821 shost = data->shost;
1823 mutex_lock(&shost->scan_mutex);
1825 if (!shost->async_scan) {
1826 printk("%s called twice for host %d", __func__,
1829 mutex_unlock(&shost->scan_mutex);
1833 wait_for_completion(&data->prev_finished);
1835 scsi_sysfs_add_devices(shost);
1837 spin_lock_irqsave(shost->host_lock, flags);
1838 shost->async_scan = 0;
1839 spin_unlock_irqrestore(shost->host_lock, flags);
1841 mutex_unlock(&shost->scan_mutex);
1843 spin_lock(&async_scan_lock);
1844 list_del(&data->list);
1845 if (!list_empty(&scanning_hosts)) {
1846 struct async_scan_data *next = list_entry(scanning_hosts.next,
1847 struct async_scan_data, list);
1848 complete(&next->prev_finished);
1850 spin_unlock(&async_scan_lock);
1852 scsi_autopm_put_host(shost);
1853 scsi_host_put(shost);
1857 static void do_scsi_scan_host(struct Scsi_Host *shost)
1859 if (shost->hostt->scan_finished) {
1860 unsigned long start = jiffies;
1861 if (shost->hostt->scan_start)
1862 shost->hostt->scan_start(shost);
1864 while (!shost->hostt->scan_finished(shost, jiffies - start))
1867 scsi_scan_host_selected(shost, SCAN_WILD_CARD, SCAN_WILD_CARD,
1872 static int do_scan_async(void *_data)
1874 struct async_scan_data *data = _data;
1875 struct Scsi_Host *shost = data->shost;
1877 do_scsi_scan_host(shost);
1878 scsi_finish_async_scan(data);
1883 * scsi_scan_host - scan the given adapter
1884 * @shost: adapter to scan
1886 void scsi_scan_host(struct Scsi_Host *shost)
1888 struct task_struct *p;
1889 struct async_scan_data *data;
1891 if (strncmp(scsi_scan_type, "none", 4) == 0)
1893 if (scsi_autopm_get_host(shost) < 0)
1896 data = scsi_prep_async_scan(shost);
1898 do_scsi_scan_host(shost);
1899 scsi_autopm_put_host(shost);
1903 p = kthread_run(do_scan_async, data, "scsi_scan_%d", shost->host_no);
1905 do_scan_async(data);
1906 /* scsi_autopm_put_host(shost) is called in scsi_finish_async_scan() */
1908 EXPORT_SYMBOL(scsi_scan_host);
1910 void scsi_forget_host(struct Scsi_Host *shost)
1912 struct scsi_device *sdev;
1913 unsigned long flags;
1916 spin_lock_irqsave(shost->host_lock, flags);
1917 list_for_each_entry(sdev, &shost->__devices, siblings) {
1918 if (sdev->sdev_state == SDEV_DEL)
1920 spin_unlock_irqrestore(shost->host_lock, flags);
1921 __scsi_remove_device(sdev);
1924 spin_unlock_irqrestore(shost->host_lock, flags);
1928 * scsi_get_host_dev - Create a scsi_device that points to the host adapter itself
1929 * @shost: Host that needs a scsi_device
1931 * Lock status: None assumed.
1933 * Returns: The scsi_device or NULL
1936 * Attach a single scsi_device to the Scsi_Host - this should
1937 * be made to look like a "pseudo-device" that points to the
1940 * Note - this device is not accessible from any high-level
1941 * drivers (including generics), which is probably not
1942 * optimal. We can add hooks later to attach.
1944 struct scsi_device *scsi_get_host_dev(struct Scsi_Host *shost)
1946 struct scsi_device *sdev = NULL;
1947 struct scsi_target *starget;
1949 mutex_lock(&shost->scan_mutex);
1950 if (!scsi_host_scan_allowed(shost))
1952 starget = scsi_alloc_target(&shost->shost_gendev, 0, shost->this_id);
1956 sdev = scsi_alloc_sdev(starget, 0, NULL);
1960 scsi_target_reap(starget);
1961 put_device(&starget->dev);
1963 mutex_unlock(&shost->scan_mutex);
1966 EXPORT_SYMBOL(scsi_get_host_dev);
1969 * scsi_free_host_dev - Free a scsi_device that points to the host adapter itself
1970 * @sdev: Host device to be freed
1972 * Lock status: None assumed.
1976 void scsi_free_host_dev(struct scsi_device *sdev)
1978 BUG_ON(sdev->id != sdev->host->this_id);
1980 __scsi_remove_device(sdev);
1982 EXPORT_SYMBOL(scsi_free_host_dev);